When those tell-tale black spots start to appear on tile, walls and fabric, you know you've got a problem: mildew, the stubborn fungus that loves to colonize dark and damp places. As warm weather brings higher humidity levels to many areas of the home, mildew can get out of control. But you don't have to resort to bleach or other toxic solutions to keep your home mildew-free. Here's how to kill mildew naturally.

Air and sunlight

Fresh air and direct exposure to sunlight will eliminate mildew, so portable items like clothing can be hung on a clothesline or placed outside. Just be sure to bring it in before it rains, which can worsen the problem for items that aren't washable.

If your mildewed bathroom or basement has a window, open it up and place a fan inside the window to get some air moving in the space and let in light. Then, get ready to attack the mildew with natural solutions like vinegar, hydrogen peroxide, tea tree oil and baking soda.

Vinegar and essential oils

White vinegar is a safe, natural and very effective mold and mildew killer. A study by a microbiologist at Good Housekeeping found that vinegar is 90 percent effective against mold, and 99.9 percent effective against bacteria.

You can either soak a sponge in full-strength vinegar, or fill a spray bottle and thoroughly soak affected areas. Let it sit for a few hours, and then scrub it with a brush or a coarse scrubbing sponge.

The smell of the vinegar will dissipate within a few hours, but if it bothers you, you can simply add some of your favorite essential oils to the spray bottle to make it more pleasant. Virtually any essential oil will work, but there are some that boost vinegar's mildew-killing power. Not only will grapefruit seed extract tone down the scent of vinegar, it has anti-fungal properties of its own, so it's an ideal addition. 

Tea tree oil may just be the greatest natural mold and mildew killer of all. While it has a strong scent and is not nearly as cheap as vinegar, it has powerful fungus-killing abilities. You can either add two teaspoons of tea tree oil to two cups of water to spray onto affected surfaces, or add a few drops to your vinegar mildew-killing solution.

Baking soda and peroxide

Baking soda is mildly abrasive, so it's ideal for scrubbing away the remnants of mildew and mold. It works especially well in tough spots like grout, where mildew can leave stains behind even after it's killed. Make a paste out of baking soda and water and simply work it into the surface with a scrub brush or sponge. Rinse with white vinegar to eliminate the white residue that baking soda leaves behind.

Hydrogen peroxide is another way to kill mildew naturally. Just apply it full-strength directly to affected surfaces, let it sit for at least ten minutes and then wipe the mildew away.

Mold and mildew preventatives

The best way to prevent mold and mildew from growing in the first place is to be vigilant about leaks. Just a little bit of water leaking from pipes, a sink, a water heater or the roof can lead to a big battle.

To prevent mildew growth in the bathroom, you can keep a spray bottle of full-strength vinegar handy. Spray down shower, bathtub and tile surfaces after each shower or bath and allow it to dry.

Another natural solution for the prevention of mold and mildew is a new product called Zep Commercial Clear Shell. This non-toxic spray uses an anti-microbial by-product of crab shells to create an invisible, long-lasting shield. Sprayed onto a surface after it has been cleaned of mold and mildew, the Clear Shell product prevents future outbreaks.

Ensure that dark, dank basements and other mildew-prone places stay as dry as possible with a de-humidifier, which can pull moisture out of the air and rob fungi of the conditions they need in order to thrive. Choose an Energy Star dehumidifier, which will do the job without consuming excessive amounts of energy. Many de-humidifiers have 24-hour timers that allow you to run them at certain intervals throughout the day.

Got other tips for how to kill mildew naturally? Leave us a note in the comments below.

Editor’s note: Zep is a Mother Nature Network sponsor.

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